Pump oiling means



Jam, 24 T15 E. RAWsoN 495,693

PUMP OILING MEANS Filed Aug. 3l, 1945 Patented Jan. 24, 1950 PUMP oILING MEANS Emanuel Rawson, Chicago,-Ill., assignor to Rite- Way Products Company, Chicago, Ill., a corporation of Delaware Application August 31, 1945, Serial No. 613,798

(Cl. 230-.2D7)

15 Claims.

This invention relates to pumps and more particularly to the oiling means for air pumps such as, for instance, a vacuum pump.

` Aair compressor pump.' The pump is indicatedat In certain types of vacuum pumps there is a E tendency for the pump lubricant to follow the air currents outwardly of the pump and be dissipated by discharge into the atmosphere. This not only necessitates frequent replenishment of the oil supply but also tends to produce disagreeable oil odors in the region of the pump and to befoul objects close by.

It is one of the objects of the present invention to provide an improved vacuum pump or pump casing wherein the above mentioned diiiiculties are obviated by providing means entirely within the pump for recirculating the oil that is initially carried oi with the air stream. It is a further object of the presentv invention to provide a simple structure wherein the tube or tubes for recirculating the oil may be easily and quickly assembled, and disassembled if necessary for cleaning.

It is a further object of the present invention to provide an improved oilng system wherein provision is made for a visual indication of Whether or not the circulating oil system is functioning.

It is a still further object of the present invention to provide an oil recirculating system with means for ltering or removing foreign matter that may be carried 01T by the oil stream.

It is a still further object-of the present invention to provide an oiling system of the above mentioned character which is substantially entirely contained within the pump casing.

The attainment of the above and further -objects of the present invention will be apparent from the following specication taken in conjunction with the accompanying drawing forming a part thereof.

In the drawing:

Figure 1 is a transverse sectional View of a rotary pump embodying the present invention;

Figure 2 is a transverse sectional view through the bottom of the oil by-pass pipe; l

Figure 3 is a sectional view illustrating a modied construction;

Figure 4 is an enlarged sectional view through the top of the oil by-pass pipe; and- Figure 5 is a view taken along the line 5-5 of Figure 2.

In the drawings like reference numerals desig# nate like parts throughout.

The pump to which the present invention is applied is a rotaryairpurnp. As shown it is a vacuum pump',-alth oug'h the invention is equally applicable tothe same pump when used as .an

land comprises an integral casing within which the rotor of the pump is mounted. The rotary portion'of the pump-is of the same construction as illustrated in the patent to McArthur et al., No. 2,313,387, issued March 9, 1943, to which reference may be had. The pump comprises a casing I0 in which is located a drum-shaped chamber I I which houses a drum-shaped rotor I2 'of smaller diameter than the diameter of the chamber II. The rotor I2 is actuated by an eccentric I3 carried by a shaft I4. The eccentric operates within a ball race I5 so that as the shaft is rotated the line of contact of the rotor I2 will progressively follow around theinner cylindrical wallof the casing II, thus progressively driving ahead the air from the point of ini-low to the point of discharge, in the manner well understood in the operation of pumps." As shown the air is drawn in'through an inlet opening pipe I6, into a vac,- uum air inlet chamber I'I which communicates with the interior of the chamber I I through a port I8 n'the' inlet side of a fin VI9 which is integral with the rotor I2 and is slidably mounted within a bearing block 2l`l`carried by a depending partition 2l which is part of the casing I.

The iin I 9 projects upwardly from the periphery of the rotor. The top of the wall of the chamber I I is divided to' form a gap through which the iin I9` projects and which gap is divided by the n into the inlet and'outlet ports I8 and 22. The depending partition 2| and the n I9 divide the upper portion of the `casing I D into two cham'- bers, one of which constitutes the inlet or vacuum Achamber II and' the other constitutes the outlet or discharge chamber 2.3.4 The discharge chamber 23 has an outlet opening 25 at the top thereof in which is threaded a rather large diameter pipe E6 constituting the outlet pipe. In thev case of a vacuum pump the outlet pipe is part of an exhaust muilier 2'1.

Adjacentthe v.bottom of the discharge chamber 23 the casing IIIv has an opening V3l), the portion of the casing, above the opening 30 extending sideways, as indicated at 3|, vto provide the casing vwith adownwardly directed opening 32. ,A

`transparent cup 34, which constitutes an oil well,

closes the opening 32. The cup is held in place by a U-shapedvyoke 35 that embraces the cup 34, the'opposite armsof the yoke 35 being swiveled to Ithe casing, and the bght portion of the yoke `3 5 -havinga thumb screw,- 3B threaded through an opening in the yoke, which thumb screw bears againstthe cup ,34 and supports it in place. A

chamber suitable rubber gasket 40 provides a sealing t between the cup 34 and the casing.

Above the partition 2| there is a small chamber or compartment t5, which has an opening 46 leading to the chamber I'I. The compartment 45 also has a tapped opening M leading to the discharge cham-ber 23, `said opening having an eX- ternally threaded sleeve 48 threaded therein through which sleeve there is extended an oil tube 5). The top of the tube opens into the compartment 45 and the bottom extends into the oil cup 34. The bottom of the tube 50 is inwardly flanged to restrict the opening of the tube so that the bottom opening of the tube 5U constitutes a fine choke 5 I. The top of the compartment 45 is closed by a plug 52 that includes a permanent magnet 53, the opposite poles of which are indicated at 54-55. The opening 41 is directed at an angle towards the oil well to facilitate assembly of the tube 50 in the casing IU. When the shaft It rotates in a counter-clockwise direction the rotor will follow the wall of the surrounding I I in a counter-clockwise direction thereby drawing air in through the pipe I6, chamber I 'I and port I8 and forcing it around the periphery of the rotor and out through the port 22 into the discharge chamber 23. The air then flows through the muier to the atmosphere. There is a tendency for the rotor lubricating oil to follow the air current and be forced out of the rotor chamber II. Some of the oil precipitates within the chamber 23 and the rest of the oil is caught in the muirler 2l and iiows downwardly through the pipe '25 into the discharge chamber 23. The oil thus tends to accumulate in the cup 34 which is part of the discharge lchamber 23. Due to the fact that the air pressure within the chamber II is below that of the air pressure within the chamber 23 oil flows through a passageway from the cup 315, through the choke 5I into the tube 58 to the chamber 45, thence through the opening 45 into the inlet chamber I'I. The oil entering the chamber 45 is directed into the region of the permanent magnet 52 which attracts and holds any ne particles of iron or iron lings that may have been carried along by the owing air. The oil leaving the opening 45 drops into the path of the air flowing through the chamber I'I and is carried thereby to the inlet port I8 and maintains the cooperating surfaces of the chamber I I and the rotor I2 lubricated.

The cup 34 provides a visual indication of the presence or absence of lubricating oil and of the amount of smudge or dirt that may have acc-umulated. The oil supply for the pump can be replenished by merely unscrewing the plug 52 and then pouring the oil into the casing.

In Figures 3 and 5 there is shown an alternate construction which differs essentially from that of Figure 1 in that the position of the cup 34 and the plug 52 of Figure l have been reversed. The pumping system of the pump of Figure 2 is the same as that of Figure 1. In this instance the side wall of the pump casing I0 is provided with an opening 'I0 at the bottom of the air discharge chamber, which opening is closed by a threaded magnetic drain plug 52, of the same construction as that of Figure l. The bottommost part 'of the discharge cham-ber 23 constitutes an oil well. A straight oil tube 'I2 is secured to a metallic plug 73 that has a choke 'I4 therethrough and which plug is threaded through a tapped opening 41 in the top of the casing Il) at the partition 2! so that the tube 'I2 and the choke lll constitutes an oil passageway from the bottom ofthe 'discharge chamber 23 to the oil chamber 45 formed at the top of the partition 2I. The oil chamber 45 is open at its top and communicates with the pump intake chamber I'I 'by means of a port 18. A sight glass, in the `form of an inverted transparent cup 19, is positioned over the open top of the cham- :ber 45 and makes a sealing fit as by a synthetic rubber gasket '8 0.

A yoke 35 in the form of a stiff spring wire bent to a U shape is swiveled to the casing IQ as by having the ends of the yoke bent in alignment to constitute both arms 92-92 pivots that extend into aligned openings in lugs 93 constituting a part of the pump casing I0. A screw 95 having a threaded shank on which is threaded a thumb screw 96 is secured on the under side of the bail portion of the yoke 35. The thumb screw 95 bears against the cup 'I9 and thus holds the cup in place.

During operation of the pump the chamber 45' is at the same vpressure as that of the intake side cf the pump. Oil will thus flow from the bottom of the discharge chamber 23 through the oil tube 'I2 land the choke Ill where it is discharged as a continuous jet against the inner surface of the sight glass 'I9 and then drops down into the chamber 45 and through the opening 'I8 into the path of ow of the incoming air.

During operation of the pump there is a violent agitation of the air owing through the discharge chamber 23, which air carries with it a large amount of oil. Oil globules are scattered in the chamber 23, there Abeing a general current or spray of oil flowing downwardly from the muler and another current or spray of oil being carried upwardly by the moving air. A large number of oil globules are continuously striking the outside of the tube 'I2 which stops their movement in the air stream and they then move downwardly along the outer surface of the tube. When they reach the bottom ofthe tube I2 they come into the path of a current of air and oil that is being drawn up into the tube. Thus any oil that strikes the outer surface of the tube and flows down the tube never drops off of the bottom of the tube but is drawn up into the tube and discharges through the choke 74. I have found that in many instances the amount of oil that thus strikes the outside of the tube 'I2 and flows down the outside of the tube and then into the tube is suicient for lubricating purposes and therefore the tube 'I2 may be so short as not quite to reach the oil level in the oil well at the bottom of the air discharge chamber 23.

In compliance with the requirements of the patent statutes I have here shown and described a few preferred embodiments of my invention. It is, however, to be understood that the invention is not limited to the precise constructions here shown, the same being merely illustrative of the principles of the invention. What is considered new and desired to be secured by Letters Patent is:

l. An air flow device comprising a casing having a top, means including a partition extending downwardly from the top of the casing and dividing the casing into an air inlet chamber and a discharge chamber, means for drawing air from the inlet chamber and discharging that air into the discharge chamber, the top of the casing having a pair of communicating openings therethrough on opposite sides of the partition and communicating with the respective chambers, an oil well at the lower part of the dis-charge chamber, a tube extending from the oil-wel1 through one of said openings, means forming a sealing cover over the portion of the top of the casing where the two openings are located whereby the preponderance of pressure in the discharge chamber over that in the inlet chamber causes oil to ow from the oil well through the tube thence through the opening that leads to the inlet chamber.

2. An air how device comprising a casing hav-- ing a top, means including a partition extending downwardly from the top of the casing and dividing the casing into an air inlet chamberv and a discharge chamber, means for drawing air from the inlet chamber and discharging that air into the discharge chamber, the top of the casing having a pair of communicating openings therethrough on opposite sides of the partition and communicating with the respective chambers, an oil well at the lower part of the discharge chamber, a tube extending from the oil well through one of said openings, the opening leading to the discharge chamber being at an angle directed towards the o-il well to facilitate insertion of the tube in the casing through the last mentioned opening, means forming a sealing cover over the portion of the top of the casing where the two openings are located whereby the preponderance of pressure in the discharge chamber over that in the inlet chamber causes oil to iiow from the oil well through the tube thence through the opening that leads to the inlet chamber.

3. An air pump comprising a casing having an air inlet chamber, an air discharge chamber, and an operating chamber, means in said last mentioned chamber for drawing air from the inlet chamber` and discharging that air into the discharge chamber, an oil well at the lower part of the discharge chamber, the top ofthe casing wall having an opening therethrough' leading into the discharge chamber, a tube extending through the opening towards the oil well, said opening being at an angle directed towards the oil well so that the tube can be put into position by insertion through said opening, a second opening in the casing wall adjacent the rst opening and leading into the inlet chamber, means including a sight glass on the outside of the casing establishing communication between said two openings.

4. An air pump comprising a casing having an air inlet chamber, an air discharge chamber,

4and an operating chamber between the inlet and the discharge chambers, means in said last mentioned chamber for drawing air from the inlet chamber and discharging that air into the discharge chamber, an. oil well at the .lower part of the discharge chamber, the top of the casing wall having an opening therethrough leading into the discharge chamber, a tube extendingthrough the opening, said opening being at an angle directed towards the oil well so that the tube can be put into position by insertion through said opening, a second opening in the casing wall adjacent the first opening and leading into the inlet chamber, means including a sight glass establishing communi-cation between said two openings, said tube and said sight glass and said second mentioned opening forming parts of an oil flow passageway from the discharge chamber to the inlet chamber, whereby the preponderance of pressure in the discharge chamber over the pressure in the inlet chamber causes oil to new from the discharge chamber through said tube and across the sight glass and thence through said second opening into the inlet chamber, said passageway having a choke therein for restricting the rate of oil flow therethrough.

5. An air pump comprising a casing having from the inlet chamber to the discharge chamber, and an operating chamber between the inlet and the discharge chambers, means in said last mentioned chamber for drawing air from the inlet chamber and discharging that air into the discharge chamber, an oil well at the lower part of the discharge chamber, the top of the casing wall having an opening therethrough leading into the discharge chamber, a tube extending through the opening towards the oil well, said opening being at anangle directed towards the oil well so that the tube can be put into position by insertion'through said opening, a second opening in the casing wall adiacent the first opening and leading into the inlet chamber, means including a part of the casing formingl a compartment `through whichboth openings are in communication, said last named means including a releasable closure closing said compartmentfrom the atmosphere, said` tube and said compartment and said second mentioned opening forming parts of an oil ow passageway from the discharge chamber to the inlet chamber, whereby the Ypreponderance of pressure in the discharge chamber over the pressure in the inlet' chamber causes oil to ilow from said well through said tube into said compartment thence through said second opening into` the inlet chamber, means forming a choke in said oil iiow passageway for restricting the rate of oil flow therethrough, there being a sight vglass member and a plug member in the path of the oil ow in said oil flow passageway, both members being secured to the casing and exposed on the outside of the casing andone of said members constitutingthe abovermentioned releasable closure. 6. A rotary air pump comprising a casing having an` air in let chamber, an air discharge chamber, and an operating chamber between the inlet and the discharge chamber, rotary pump mechanism in said last mentioned chamber for drawing air from the inlet chamber and dischargin it into the discharge chamber, an oil well at the lower Vpart of the discharge chamber, the top of the casing wall having an opening therethrough leading into the discharge chamber, a tube extending through the opening towards the voil well, said opening being at an angle directed towardsthe oil well so that the tube can be put into position by insertion through said opening,

a` second opening inthe casing wall adjacent the rst opening and leading intothe inlet chamber, means including a part of the casing forming a compartment through which both openings are in communication, said last named means including a releasable closure closing said compartment from the atmosphere, said tube and said compartment and said second mentioned opening forming parts of an oil flow passageway from the discharge chamber to the inlet chamber, whereby the preponderance of pressure in the discharge chamber over the pressure inthe inlet chamber causes oil to iiowl from said well through said tube into' said'compartment thence through said second opening into the inlet chamber, said second opening-discharging oil into the path of air flow in the inlet chamber, means forming a choke in said oil 'flow passageway `for restricting the rate of oil iiow therethrough, there being a sight -glassmember andV a magnetic "plug member in I the path of the oil flow in said oil flow passageway, both members being secured to the casing and exposed on the outside of the casing and one of said members constituting the above mentioned releasable closure.

7. An air ow device comprising a casing provided with an air inlet chamber and an air discharge chamber, means for drawing air from the inlet chamber and discharging air into the discharge chamber, an oil well at the lower part of the discharge chamber, means forming an oil passageway within the casing and extending from the oil well to and opening into the air inlet chamber in the path of air flow therein, said oil passageway having a choke therein for restricting the rate of ow of oil therethrough, said casing having an opening at the top thereof communicating with said passageway and a releasable closure for said opening.

8. An air flow device comprising a casing provided with an air inlet chamber, and an air discharge chamber, means for drawing air from the inlet chamber and discharging air into the discharge chamber, an oil well at the lower part of the discharge chamber, means forming an oil passageway within the casing and extending from the oil well to and opening into the air inlet chamber in the path of air flow therein, said oil passageway having a choke therein for restricting the rate of flow of oil therethrough, said casing having an opening communicating with said passageway and a releasable closure plug for said opening, said closure plug having a magnetic member in the path of oil owing through said passageway for removing iron particles from said flowing oil.

9. An air flow device comprising a casing having a top, means including a partition extending downwardly from the top of the casing and dividing the casing into an air inlet chamber and a discharge chamber, means for drawing air from the inlet chamber and discharging that air into the discharge chamber, the top of the casing having a pair of openings formed therethrough on opposite sides of the partition and communicating with the respective chambers, a tube extending into the discharge chamber from one of said openings, means forming a cover overlying the portion of the top of the casing where the two openings are located and together with a portion of the casing forming a compartment into which both openings lead whereby the preponderance of pressure in the discharge chamber over that in the inlet chamber causes oil at the bottom of the tube to flow into the compartment through the tube thence through the opening that leads to the inlet chamber.

10. An air flow device comprising a casing having a top, means including a partition extending downwardly from the top of the casing and dividing the casing into an air inlet chamber and an air discharge chamber, means for forcing air from the inlet chamber to the discharge chamber, a pair of ports opening into the respective chambers, the top of the casing having an opening through which the ports are in communication with each other, a tube extending into the discharge chamber from one of said ports and discharging into said opening, and means forming a releasable sealing cover for said opening in the top of the casing, whereby the discharge flowing from said tube into said opening then flows into the inlet chamber through the port leading thereto from said opening.

1l. An air flow device comprisinga casing having a top, means including a partition extending downwardly from the top of the casing and dividing the casing into an air inlet chamber and an air discharge chamber, means for forcing air from the inlet chamber to the discharge chamber, a pair of ports opening into the respective chambers, the top of the casing having an opening through which the ports are in communication with each other, a tube extending into the discharge chamber from one of said ports and discharging into said opening, means forming a releasable sealing cover for said opening in the top of the casing, whereby the discharge flowing from said tube into said opening then flows into the inlet chamber through the port leading thereto from said opening, said cover comprising a sight glass.

l2. An air flow device comprising a casing having a top, means including a partition extending downwardly from the top of the casing and dividing the casing into an air inlet chamber and an air discharge chamber, means for forcing air from the inlet chamber to the discharge chamber, a pair of ports opening into the respective chambers, the top of the casing having an opening through which the ports are in communication with each other, a tube extending into the discharge chamber from one of said ports and discharging into said opening, means forming a releasable sealing cover for said opening in the top of the casing, whereby the discharge nowing from said tube into said opening then flows into the inlet chamber through the port leading thereto from said opening, said cover comprising a magnet in the path of fluid owing through said opening.

13. An air ow device comprising a casing having therein means dividing the same into an air inlet chamber and an air discharge chamber and means for forcing air from the inlet to the discharge chamber, a uid flow passageway at the outer surface of the casing and ports leading from the respective chambers to said passageway and communicating with one another through said fluid iiow passageway, and a releasable closure for the portion of the outer surface of the casing that constitutes said passageway, the port leading to the discharge chamber being a straight port having a longitudinal axis which intersects the releasable closure.

14. An air flow device comprising a casing having therein means dividing the same into an air inlet chamber and an air discharge chamber and means for forcing air from the inlet to the discharge chamber, a fluid flow passageway at the outer surface of the casing and ports leading from the respective chambers to said passageway and communicating with one another through said fluid ow passageway, and a releasable closure for the portion of the outer surface of the casing that constitutes said passageway, said releasable closure including a sight glass.

l5. An air flow device comprising a casing having therein means dividing the same into an air inlet chamber and an air discharge chamber and means for forcing air from the inlet to the discharge chamber, a fluid flow passageway at the outer surface of the casing and ports leading from the respective chambers to said passageway and communicating with one another through said uid flow passageway, and a releasable closure for the portion of the outer surface of the casing that constitutes said passageway, said re- 9 leasable closure including a magnet in the path Number of ud flow through said passageway. 1,558,788 EMANUEL RAWSON. 1,967,957 2,233,017 REFERENCES CITED 5 2,313,337 The following references are of record in the le of this patent:

UNITED STATES PATENTS Nunsle' Number Name Date 10 1,148,809 White Aug. 3, l1915 Name Date Campbell Oct. 27, 1925 Lucas July 24, 1934 Lambin Feb. 25, 1941 McArthur et al Mar. 9, 1943 FOREIGN PATENTS Country Date France Apr. 7, 1913 

